19026421 has 2 divisors, whose sum is σ = 19026422. Its totient is φ = 19026420.

The previous prime is 19026401. The next prime is 19026437. The reversal of 19026421 is 12462091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19018321 + 8100 = 4361^2 + 90^2 .

It is an emirp because it is prime and its reverse (12462091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19026421 - 2⁵ = 19026389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19026401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9513210 + 9513211.

It is an arithmetic number, because the mean of its divisors is an integer number (9513211).

Almost surely, 2^19026421 is an apocalyptic number.

It is an amenable number.

19026421 is a deficient number, since it is larger than the sum of its proper divisors (1).

19026421 is an equidigital number, since it uses as much as digits as its factorization.

19026421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 19026421 is about 4361.9285872192. The cubic root of 19026421 is about 266.9637950226.

The spelling of 19026421 in words is "nineteen million, twenty-six thousand, four hundred twenty-one".